Traditionally, as a storage system that achieves a storage device with a flexible volume configuration and memory capacity without being restricted by a volume configuration and memory capacity of a physical storage device, storage for a virtual environment or a so-called virtual storage device exists. The virtual storage device has therein actual storage that controls access to the physical storage device. The virtual storage device generates a virtual volume by a processor device that manages the actual storage.
The virtual volume is formed on the processor device within the virtual storage device and associated with a physical storage region on the actual storage. In addition, a processor device that is among a plurality of processor devices and serves as an agent is configured to control a driver and monitor events such as errors and notify a processor device serving as a manager of the events. The processor device that serves as the manager is one of the processor devices within the virtual storage device and manages configuration information on the virtual volume and the state of the virtual volume and plays a role in controlling the agent.
In the virtual storage device, a segment that forms the virtual volume is mirrored for a case where a failure occurs in the actual storage storing data, for example. The segment is a region having a certain size and storing data extracted from a logical unit number (LUN) of the actual storage. Upon the occurrence of a failure, the virtual storage device continuously executes access in order from a segment belonging to a failed LUN via a segment that stores data obtained by mirroring and is assigned to belong to another LUN, and the virtual storage device improves the availability of the storage.
As a related conventional technique, there is a technique for executing a process of restarting an I/O process if storage is blocked upon the detection of an error of the I/O process executed on the storage and executing a process of blocking the storage if the storage is not blocked and the frequency at which an error occurs is equal to or higher than a predetermined value. In addition, there is a technique for copying a pool providing a virtual volume per unit of volume that forms the pool and switching a blocked volume to a copied volume in the pool if a physical device is blocked.
As examples of the related art, Japanese Laid-open Patent Publications 2014-215990 and 2010-092259 are known.